Autopsy findings in AIDS — A histopathological analysis of fifty cases

Summary Fifty consecutive AIDS autopsy cases were evaluated. All subjects showed one or more opportunistic infections and malignancies included in the AIDS case definition with cytomegalovirus and Kaposi's sarcoma being most prevalent. Mycobacterial and cryptococcal infections occurred only infrequently. Most patients of our series after successful treatment ofPneumocystis carinii pneumonia or cerebral toxoplasmosis later succumbed to less treatable conditions like disseminated cytomegalovirus or fungal infections or malignant lymphoma. In the absence of specific treatment for the HIV infection leading to these lethal complications special emphasis must be put on the prevention of HIV transmission and spread.Abbreviations AIDS Acquired immune deficiency syndrome - CDC Centers for Disease Control - CMV Cytomegalovirus - CNS Central nervous system - HIV Human immunodeficiency virus - KS Kaposi's sarcoma - ML Malignant lymphoma - PCP Pneumocystis carinii pneumonia     

Opportunistic infections in adults with acquired immunodeficiency syndrome: a comparison of clinical and autopsy findings.

BACKGROUND AND PURPOSE: Many opportunistic infections causing death in acquired immunodeficiency syndrome (AIDS) patients are often not diagnosed prior to death. The objective of this study was to compare the premortem and postmortem diagnoses of opportunistic infections and tumors among 15 AIDS patients treated in a hospital in southern Taiwan. METHODS: Total autopsy (brain, chest and abdominal cavity) was performed in 2 patients, and partial autopsy in 13. RESULTS: Pneumocystis carinii pneumonia, candidiasis, lymphoma, Kaposi's sarcoma, toxoplasmosis and salmonellosis were more commonly diagnosed before death than at autopsy. By contrast, cytomegalovirus (CMV) infections and herpes simplex virus or varicella-zoster virus infections were more frequently diagnosed at postmortem examinations than prior to death. CONCLUSIONS: In conclusion, this study found substantial discrepancies between autopsy findings and premortem clinical diagnoses in AIDS patients, especially for CMV infection.     

Clinical experience of HIV/AIDS in a municipal hospital in Taiwan

To describe the spectrum of epidemiological and major clinical manifestations of patients infected by human immunodeficiency virus type 1 (HIV-1) in a municipal hospital, a retrospective review was done of 53 HIV-1-infected patients who had been admitted to Taipei Municipal Jen-Ai Hospital between January 1990, and July 1996. The majority (94.3%) of the patients in the cohort were male. Peak incidence was found in the fourth decade (28.3%). Forty-four (83%) patients presented in the first hospital stay with acquired immunodeficiency syndrome (AIDS). The mean duration between establishment of diagnosis of HIV-1 infection and that of AIDS was 11.2 (0-84) months. Heterosexual transmission accounted for 54.7% of the infections in the study group, and bi-/homosexual men made up another 32%. Psychosis of new onset was noted in two patients. In all AIDS indicator conditions, Pneumocystis carinii pneumonia (PCP) was the leading opportunistic infection among AIDS patients. PCP was also on the top of initial manifestations of HIV-1 infection. One patient with Penicillium marneffei infection was diagnosed to have AIDS. The mean CD4 count at admission of AIDS patients was much lower than that of non-AIDS patients (32 vs. 297/microliter, p < 0.0005). During the follow-up period 24 of 53 patients died. Mean survival time of 23 expired patients after establishment of diagnosis of AIDS was 6.4 (0-29) months. The results indicated that males outnumbered females greatly in the number of cases. Sexual activity remained the most important route of infection. Psychosis of new onset may be an early manifestation of HIV-associated encephalopathy and requires more attention. In addition, the outcome was poor as most patients in this area did not become aware of risk of HIV-1 infection until they were seriously illed with full-blown AIDS that they would seek medical help. PCP was the most common incentive for medical consultation. Penicillium marneffei infection is endemic in southeast Asia, and should be classified as an AIDS indicator condition in Taiwan.     

Cytomegalovirus infection in classic, endemic and epidemic Kaposi's sarcoma analyzed by in situ hybridization.

In order to evaluate the association between cytomegalovirus (CMV) infection and Kaposi's sarcoma (KS) at the cellular level, four classic KS, five endemic (African) KS and 55 epidemic KS from 12 patients with AIDS were analyzed by in situ hybridization with a biotinylated specific CMV-DNA probe. CMV-DNA was sparsely demonstrated in the sarcomas in 10 of the patients with AIDS but in none of the classic or endemic sarcomas. The distribution and localization of the CMV-infected cells did not suggest CMV as a major pathogenic stimulus for the development of KS but rather as an opportunistic infection in severely immunosuppressed patients.     

Epidemiology and clinical features of HIV infection/AIDS in Korea

HIV infection/AIDS shows characteristic epidemiological and clinical patterns according to the region, country, and race. The epidemiological and clinical patterns of HIV infection/ AIDS in Korea was investigated by retrospectively analyzing the medical records of 176 HIV-infected persons who visited two major referral hospitals of AIDS in Korea from 1985 to April 2000. The most common transmission route was heterosexual contact (52.3%), followed by homosexual contact (23.9%). Among the opportunistic diseases, candidiasis was the most prevalent (21.6%), followed by Pneumocystis carinii pneumonia (15.9%), tuberculosis (12.5%), and CMV infection (9.1%). The most common initial AIDS-defining opportunistic disease was tuberculosis (33.3%). The most common causes of death were tuberculosis (25.7%) and Pneumocystis carinii pneumonia (25.7%). This study describes the epidemiological and clinical patterns of HIV infection/AIDS in Korea, which not only enables us to accurately understand HIV infection/ AIDS in this country, but eventually to aid in establishing effective preventive measures and treatment guidelines in Korea.     

210例HIV/AIDS患者淋巴细胞计数与机会性感染相关分析

目的分析HIV/AIDS患者总淋巴细胞计数（TLC）与机会性感染的关系,为HIV/AIDS患者机会性感染的治疗及一级、二级预防提供参考依据。方法对2009年6月至2011年5月210例HIV/AIDS患者的淋巴细胞及出现的机会性感染进行分析。将患者分为TLC〉1300个/μl组（G1组）和TLC≤1300个/μl组（G2组）,比较两组患者机会性感染发生率的差异。结果 210例HIV/AIDS患者机会性感染的总感染率为86.7%,主要的机会性感染为口腔念珠菌感染（56.2%）、细菌性肺炎（46.7%）、肺结核（42.4%）、败血症（21.4%）、感染性腹泻（20.5%）。G2组患者机会性感染的发生率为93.6%,高于G1组患者（55.3%）,差异有统计学意义（P〈0.05）;随着TLC的下降,患者发生机会性感染的机率增高。结论 HIV/AIDS患者机会性感染的发生率高,TLC是HIV/AIDS患者发生机会性感染的独立危险因素。因此,应定期监测HIV/AIDS患者TLC,加强患者机会性感染的一级和二级预防。     

Viral participation in cellular and microenvironmental transformation and amplification towards malignancy in AIDS patients

HIV-1 infection would initially predispose to neoplastic transformation in terms of a progressive lymphocytic proliferation followed by the onset of an immunodeficiency state. Both virion genomic integration and also active host cell proliferation would perhaps participate in the establishment of an often multifocal primary CNS lymphoma of AIDS type. Repeated opportunistic infections in AIDS patients tend to especially involve the central nervous system to also carry an increased risk of neoplastic transformation of the reactive B lymphocytes reaching the brain. A microenvironmental set of circumstances in patients with AIDS would predispose to non-Hodgkin's lymphoma largely in terms of an HIV-1 infection that progresses concurrently with evolving cell replication, immunodeficiency, and repeated opportunistic infections as caused by several different potential pathogens. Epstein-Barr virus infection in particular appears closely related to Hodgkin's disease that develops in some AIDS patients. A viral role in the development of lymphomas and of Kaposi sarcoma in HIV-infected individuals would account for neoplastic aggressiveness and for a particular predilection for primary CNS lymphoma. Such a role perhaps implicates viral integration within the genome of host cells that are actively proliferating or else infected by multiple viral pathogens such as EBV, HIV-1, CMV, and Herpes virus.     

Pulmonary complications of the acquired immunodeficiency syndrome: a clinicopathologic study of 70 cases

The pulmonary complications of 70 patients with the acquired immunodeficiency syndrome (AIDS) are reviewed. Pneumocystis carinii pneumonia (PCP), present in 67 per cent of the patients, was diagnosed by fiberoptic bronchoscopy with transbronchial biopsies in all of the patients except two adults, who required open lung biopsy, and two children, in whom the infection was detected only at autopsy. Other opportunistic infections, such as cytomegalovirus pneumonitis, mycobacterial infections, invasive candidiasis, toxoplasmosis, cryptococcosis, and histoplasmosis, were more difficult to diagnose by fiberoptic bronchoscopy. In only four cases were these conditions detected during life. Neoplasms and lymphoproliferative processes also presented diagnostic problems, and only one case each of Kaposi's sarcoma and lymphoid interstitial pneumonitis were detected by fiberoptic bronchoscopy. In four other cases these conditions, as well as two pulmonary lymphomas, diffuse large cell immunoblastic type, were detected only at autopsy. Sixty-eight per cent of the patients in this study died, usually with progressive intractable respiratory failure and pulmonary complications that had not been diagnosed during life, including potentially treatable diseases, such as bacterial pneumonias, PCP, nontuberculous mycobacteria, invasive candidiasis, toxoplasmosis, and invasive aspergillosis. The need for earlier detection of pulmonary complications in patients with AIDS is discussed.     

Necropsy findings in acquired immunodeficiency syndrome: a comparison of premortem diagnoses with postmortem findings

Necropsies were performed in 12 patients who fulfilled the Centers for Disease Control (CDC) criteria for acquired immunodeficiency syndrome (AIDS), and the postmortem findings were compared with the premortem diagnoses. All of the patients were men with a male sexual preference and histories of multiple episodes of venereal diseases. Four patients were intravenous drug abusers, while two abused amyl nitrate. All 12 of the patients had evidence of cellular immune deficiency at presentation. The causes of death were a variety of opportunistic infections and neoplasms. Pneumocystis carinii pneumonia was diagnosed prior to death in seven patients. Despite current therapy, all seven of those patients had persistent Pneumocystis carinii pneumonia at necropsy, as well as clinically undiagnosed cytomegalovirus infection. In addition, two cases of acid-fast infections, two of visceral candidiasis, one of pneumocystis pneumonia, one of central nervous system lymphoma, one of gram-negative bacterial pyelonephritis, and one of cutaneous aspergillosis were clinically unrecognized and untreated. Nine patients died with two or more infections. Thus, necropsy is a valuable tool for recognizing clinically undiagnosed infections and malignant disorders in AIDS.     

Spectrum of opportunistic infections in AIDS cases

Human Immunodeficiency viruses are the initial causative agents in AIDS, but most of the morbidity and mortality in AIDS cases result from opportunistic infections, Identification of such pathogen is very important for clinicians and health planners to tackle the AIDS epidemic in more effective manner. The present study describes the clinical and laboratory profile of 100 AIDS causes who presented to a referral hospital. Oral candidiasis (59.00%) was found to be the most common opportunistic infection, followed by tuberculosis (56.00%), Cryptosporidium infection (47.00%) and Pneumocystis carinii (7.00%). Presence of oral candidiasis and weight loss is highly predictive of low DC4 count and can be considered as a marker of HIV disease progression. The patients coinfected with HIV and tuberculosis are also on rise. Recognition of dual infection and taking adequate steps to deal with this epidemic is needed. As Cryptosporidium infection was detected in large number, provision of safe drinking water and maintaining good hygiene is important for prevention. Early diagnosis of opportunistic infection and prompt treatment, delays the progression towards AIDS. 91.00% of patients were infected with HIV1 and 4.00% had HIV2 infection and 5.00% were dully infected. 87.00% of patients were males and 13.00% were belonging to 21-40 years of age. Majority of them were belonging to lower socioeconomic status and heterosexual route of transmission was the commonest mode of spread.     

Autopsy findings in the acquired immunodeficiency syndrome (AIDS). A report of 395 cases from the south of France.

Necropsy findings in 395 adult patients with the acquired immunodeficiency syndrome (AIDS) who died in Nice, France, between March 1983 and May 1996 were compared retrospectively with antemortem diagnoses, risk factors and number of positive T CD4 lymphocytes at the time of death. Special emphasis on bacterial infections was made in this study. Lesions observed from 1983 through 1989 and from 1990 through 1996 were compared. We assessed the role of organ lesions in the immediate cause of death. The organ system distribution of major opportunistic infections and neoplasms was similar throughout the years of the study. The most common diagnostic disease entities in all organ sites were cytomegalovirus infection, toxoplasmosis and candidiasis. Toxoplasmosis was more common in the intravenous drug abuser group. Bacterial infections were frequent and contributed to the mortality and morbidity of all risk factor groups. Kaposi' sarcoma continued to occur more frequently in the homosexual population. Cytomegalovirus infection remained one of the most common causes of death from 1983 to 1996. Mortality from fungal and bacterial infections, and mycobacteriosis increased in frequency during the course of this study whereas deaths from pneumocystosis declined. The death rate from malignant lymphoma and carcinoma increased after 1989. The clinical cause of death concurred with the pathological cause in 55% of the cases. Lung was the most frequent organ involved followed by the central nervous system the gastrointestinal tract and the heart.     

The adrenal gland in AIDS

The adrenal gland has been known to be a common site of opportunistic infections and tumors that define the acquired immunodeficiency syndrome (AIDS) ever since the first autopsy data were published. We have examined the adrenal glands of 66 AIDS patients autopsied in New York City and tabulated and graded the findings in an attempt to estimate the likelihood of adrenal insufficiency developing on the basis of these lesions. AIDSdefining conditions were found in the adrenal glands of 56% of patients, primarily opportunistic infections (53%) and much less frequently neoplasms (3%). Cytomegaloviral (CMV) infection was by far the most common type (42%), followed by mycobacterial (8%) and fungal infections (3%). There was one case eachof Kaposi’s sarcoma and lymphoma. Total necrosis of adrenal cortex was restricted to 2 cases of tuberculosis. CMV adrenalitis, although the most common infection and often associated with necrosis, never resulted in more than 30% destruction of the cortex. We conclude that although histopathological evidence of adrenal disease is common in AIDS, most such lesions are not sufficiently extensive to result in adrenal insufficiency. In contrast to previous reports stressing the importance of CMV adrenalitis as a possible cause of adrenocortical insufficiency, we now find tuberculosis the more likely cause of total cortical destruction.     

Mycobacterium avium-intracellulare infection and immunoblastic sarcoma in a fatal case of AIDS

A pleomorphic bacterium exhibiting both acid-fast rod forms and non-acid-fast coccal forms, and identified as Mycobacterium avium-intracellulare was cultured from a facial lesion diagnosed as immunoblastic sarcoma. The patient was a 36 year-old homosexual man who died of the acquired immune deficiency syndrome (AIDS). In addition, the patient had pre-existing cutaneous lesions of Kaposi's sarcoma (KS), and was treated for probable but never proven, Pneumocystis carinii pneumonia (PCP). Variably acid-fast coccoid forms, and extremely rare acid-fast rods were demonstrated within the microscopic sections of the immunoblastic sarcoma. Similar-staining coccoid forms were also observed within the microscopic sections of the pre-existing KS tumors, and within the lung biopsy material showing inflammation suggestive of PCP. These findings, along with previously reported findings of similar bacterial forms in vivo in other cases of KS and AIDS, again suggest that variably acid-fast bacteria may play a role in the development of malignant tumors and inflammatory lung disease, which frequently occur in homosexual men with AIDS.     

Sequential serological studies of homosexual men with and without HIV infection. Epstein-Barr virus activation preceding and following HIV seroconversion.

Viral cofactors may be important in the pathogenesis of HIV infection and the development of AIDS, but their role is still imperfectly understood. Sequential serological studies were performed in a cohort of 100 homosexual men and 70 matched healthy controls over a mean period of 4 years. Of the patients, 18 were found to be HIV+ on admission to the study and 15 seroconverted to HIV+ during the follow up (seroconversion group). Serum antibodies of both IgG and IgA isotypes against Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were determined. IgG antibodies indicate past infection, while a marked increase in IgG titre or a positive IgA titre were taken to indicate active infection or reactivated latent infection. EBV and CMV infections were about two to four times more prevalent in the homosexual men both HIV- and HIV+, compared with controls. Active infections were increased in the homosexual men and particularly in the HIV+ patients. The seroconversion group revealed activation of both EBV and CMV following HIV infection. When the antibody profile of seroconverting patients at the time preceding seroconversion was compared with a matched group of 39 homosexual men who remained HIV-, no change was found in CMV antibodies, but four out of 15 (26.6%) of the patients had high titres of anti-EBV IgA preceding seroconversion, as compared with only one out of 39 (2.6%) of HIV- homosexual men (P less than 0.05). This suggests a role for EBV reactivation in the pathogenesis of HIV infection in some patients.     

The acquired immune deficiency syndrome: An international health problem of increasing importance

Summary The Acquired Immune Deficiency Syndrome (AIDS) is a new disease which first appeared in human populations about 1979. The disease is defined by the development of unusual types of cancer (e.g. Kaposi's sarcoma), or severe cellular immunodeficiency manifested by opportunistic infections (e.g.Pneumocystis carinii infection), or both. Although the etiology of AIDS is unknown, the epidemiologic evidence is consistent with an infectious agent transmitted by blood (e.g. transfusion, needle sharing) or sexual intercourse. Over three-quarters of the cases have been in homosexual or bisexual males and in intravenous drug abusers; about 5% of cases do not have recognized risk factors. A small number of cases have resulted from transfusion of blood or blood products. The early clinical manifestations are non-specific, and may include asymptomatic skin lesions, dyspnea and dry cough, weight loss, chronic diarrhea, and focal and non-focal central nervous system findings. Treatment for the associated cancers and opportunistic infections may be successful in individual instances, but the underlying immunosuppression of AIDS appears to progress inexorably and the fatality rate approaches 100% within a few years from diagnosis. Although nosocomial transmission has not been documented, infection control guidelines have been developed by analogy with hepatitis B infection.Abbreviations AIDS Acquired Immune Deficiency Syndrome - CDC Center for Disease Control - H:S ratio T helper cell to T suppressor cell ratio - CT Computerized tomography - D.M. Deutch marks - HBIG Hepatitis B Immune Globulin - KS Kaposi's sarcoma - PCP pneumocystis pneumonia - mg milogram - kg kilogram     

Malignant lymphomas in HIV-seropositive patients. Frequency,features, and prognosis. Report on 31 cases

Summary In a random HIV-seropositive population, malignant lymphomas were diagnosed in 31 patients, of whom 24 (77%) had non-Hodgkin lymphoma (NHL) and 7 (23%) Hodgkin lymphoma (HL). The prevalence of NHL among AIDS patients was 8% (23/279 cases), with a prevalence of 17% among autopsied patients (16/96 cases). No patient with HL had AIDS at the time of diagnosis. In 7 of 23 AIDS patients with NHL (30%) the diagnosis was made only post mortem; among these were all 5 patients with primary CNS NHL. Median survival from the time of diagnosis was 1 month for patients with NHL and 3 months for those with HL. In individual patients, survival for several years may be possible with chemotherapy. Certain patients with NHL appear to benefit from intensive chemotherapy with a combination of methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOPB protocol). Appropriate, therapeutic strategies taking into account the patients' individual conditions, including the overall prognosis, urgently requires development. Metastatic CNS involvement, which was the primary cause of death in 5 of 11 patients with NHL (45%) receiving chemotherapy, represents a serious limitation to successful treatment.Abbreviations AIDS acquired immunodeficiency syndrome - CB centroblastic - CDC Centers for Disease Control - CHOP cyclophosphamide, doxorubicin, vincristine, prednisone - CMV cytomegalovirus - CNS central nervous system - COPBLAM cyclophosphamide, vincristine, prednisone, bleomycin, doxorubicin, procarbazine - COPP/ABVD cyclophosphamide, vincristine, prednisone, procarbazine/doxorubicin, bleomycin, vinblastine, darcarbazine - CR complete remission - CT computerized tomography - ELISA enzyme-linked immunosorbent assay - HIV human immunodeficiency virus - HL Hodgkin lymphoma - IT intrathecal - IMVP16 ifosfamide, methotrexate, etoposide - KC Kiel classification - MACOP-B methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, bleomycin - ML malignant lymphoma - NHL non-Hodgkin lymphoma - OI opportunistic infection - PCP Pneumocystis carinii pneumonia - PD progressive disease - PR partial remission - RT radiation therapy - WBC white blood cells - WF Working Formulation     

Defective T-cell response to PHA and mitogenic monoclonal antibodies in male homosexuals with acquired immunodeficiency syndrome and itsin vitro correction by interleukin 2

We studied the ability of phytohemagglutinin (PHA) and two anti-T-cell monoclonal antibodies OKT3 and Pan T2, to induce proliferation and interleukin 2 (IL2) production in peripheral blood lymphocytes (PBL) from 21 homosexual patients: 12 with Kaposi's sarcoma (KS), 4 with reactive lymphadenopathy, and 5 with opportunistic infections. All patients with KS and opportunistic infections had significantly lower mitogen-stimulated DNA synthesis, as compared to the controls, irrespective of the mitogen used (P less than 0.01). The patients with lymphadenopathy exhibited significantly lower responses only in the OKT3 assay as compared to normals (P = 0.009). The production of endogenous IL2 was significantly lower in PBL cultures from patients with KS and with opportunistic infections, irrespective of the mitogen used, as compared to healthy male controls, and also significantly lower in the Pan T2-stimulated cultures from patients with lymphadenopathy. The addition of highly purified IL2 was able to restore partially lymphocyte proliferation in vitro in the presence of these mitogens in all patients. Our studies demonstrate (1) that male homosexuals even without clinical manifestations of immunodeficiency frequently exhibit a proliferative T-cell defect when anti-T-cell monoclonal antibodies rather than PHA are used as mitogens, (2) that this proliferative defect is associated with defective IL2 production, and (3) that this defect is at least in part correctable in vitro by highly purified IL2.     

Clinical and biological consequences of human immunodeficiency virus (LAV) infection in 15 Congolese subjects

We report 15 cases of symptomatic HIV infection seen in Paris between June 1983 and June 1985 in Congolese patients. The first signs were diarrhea, weight loss, fever, pruritis. Disseminated lymphadenopathy was frequent. Twelve patients had AIDS, and the opportunistic infections were: isosporosis, oesophageal candidiasis, cerebral toxoplasmosis, Kaposi's sarcoma, CNS' cryptococcosis, cutaneo-mucosal.     

Clinical and pathologic findings of the liver in the acquired immune deficiency syndrome (AIDS)

Clinical data and histologic sections of the liver, including immunohistochemical studies for hepatitis B surface and core antigens, were reviewed in 42 autopsy cases of the acquired immune deficiency syndrome (AIDS). Hepatomegaly, elevation of serum transaminases, and mild elevation of alkaline phosphatase were commonly observed clinical and biochemical abnormalities. Mildly elevated alkaline phosphatase and normal bilirubin levels were present in patients with Mycobacterium avium-intracellulare (MAI) infection, cytomegalovirus (CMV) infection, and Kaposi's sarcoma (KS). Histologic sections demonstrated liver involvement by MAI in eight cases; KS in six cases; cryptococcus in three cases; and CMV in two cases. One case of MAI infection was associated with marked central vein sclerosis, a finding previously unreported. Thirty-two (76%) of 42 cases had serologic or pathologic evidence of hepatitis exposure. Two patients had histologic evidence of chronic active hepatitis. The pathologic processes involving the liver appeared to be secondary to the infections and neoplasms for which this population is susceptible and did not significantly contribute to morbidity or mortality. No findings specific or pathognomic for AIDS were identified in the liver.     

Localisation of HHV-8 in AIDS related lymphadenopathy.

BACKGROUND: Many lymph node abnormalities have been described in AIDS. These include opportunistic infections that sometimes result in spindle cell pseudotumours, Kaposi's sarcoma (KS), malignant lymphoma (Hodgkin's and non-Hodgkin's), and florid reactive hyperplasia. Among these, reactive hyperplasia is the most common manifestation of AIDS related lymphadenopathy. AIM: To examine whether human herpesvirus 8 (HHV-8), the aetiological agent of KS, can be localised in AIDS related lymphadenopathy and whether its appearance in such nodes is predictive of Kaposi's sarcoma development. METHODS: A series of human immunodeficiency virus (HIV) positive men (n = 21) with AIDS related lymphadenopathy who at the time of presentation had KS or subsequently developed KS (n = 5) were examined. The prevalence of HHV-8 was assessed in these patients using solution phase polymerase chain reaction (PCR), real time TaqMan quantitative PCR, and in cell amplification techniques (PCR in situ hybridisation (PCR-ISH) and labelled primer driven in cell amplification). RESULTS: Using standard solution phase PCR in a nested format, only two of the 21 patients with AIDS related lymphadenopathy were positive for HHV-8. The lymph node of one of these patients contained KS lesions. Three HHV-8 positive patients were identified using TaqMan PCR (the original two positive patients and one additional patient). All of the positive patients either subsequently developed KS (n = 2) or had KS at the time of diagnosis (n = 1). Two additional patients subsequently developed KS, but were negative for HHV-8 by solution phase PCR and TaqMan PCR. Using PCR-ISH, HHV-8 amplicons were identified in some lymphoid cells (in one patient) and in spindle cells of the KS lesion in another. The positive lymphoid cells were predominantly concentrated in B cell areas of the affected lymph nodes, confirming the B cell tropism exhibited by HHV-8. CONCLUSIONS: The presence of HHV-8 in AIDS related lymphadenopathy is predictive of KS development and probably represents seeding of HHV-8 infected B cells from the peripheral blood. These findings support a role for HHV-8 in the pathobiology of KS.